Serving as a standard input/output interface, a universal serial bus (USB) interface has been widely applied to various electronic devices. As the USB transmission rate is gradually improved, differential signal terminal pairs are correspondingly used in a USB connector to transmit a high frequency signal. Currently, a USB connector generally includes a body made of plastic and two rows of terminals disposed in the body. The body includes a base and a tongue extending forward from the base. The two rows of terminals are respectively disposed on upper and lower surfaces of the tongue, and each row of terminals includes a differential signal terminal pair. Two adjacent terminals of a same row of terminals are separated by a plastic material. In this type of structure, the differential signal terminal pair is surrounded by a lot of plastic, the attenuation action of plastic on the high frequency signal is great, and a small part of differential signal terminals are exposed to air, so that the insertion loss, the return loss and the crosstalk of the high frequency signal in a transmission process are affected, which is adverse to transmission of the high frequency signal.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.